Introduction to Chemistry

Atoms & Elements Molecules Electrostatic charges Mixtures & compounds States of Matter Separating Mixtures Dissolving & Solutions

All matter is made up of

around 100 different elements

Name the only non-metal conductor of electricity.

Graphite (a form of carbon)

what is graphite?

A form of carbon

Elements are shown in

The Periodic Table,

How does solubility change with temperature?

solubility increases with temperature

A group of elements is..

vertical column in the Periodic Table

Miscible

Describes liquids that are soluble in each other

Immiscible

liquids that are not soluble in each other (e.g. oil & water)

A period of elements is

a horizontal row in the PT

Elements are represented by...

a chemical symbol

The typical properties of metals are..

shiny, good conductors of electricity and heat, malleable and ductile, and usually solid at room temperature.

Where on the Periodic Table (PT) are metals found)?

On the left, middle and bottom

Non-metals are found..

in the top right of the Periodic Table.

The typical properties of nonmetals are..

dull, poor conductors of electricity and heat, brittle and usually Solid or gaseous at room tem erature.

Compounds contain...

two or more elements chemically combined in fixed proportions

The properties of compounds are...

different to the elements they contain

A mixture consists of..

two or more elements or compounds not chemically combined together,

The chemical properties of each substance in the mixture..

are unchanged.

The simplest type of particle is..

an atom

Molecules are:

larger particles made from 2 or more atoms bonded together. The atoms can be the same or different.

Ions are..

particles with an overall charge formed from atoms or molecules.

Elements have particles with..

only one type of atom

Particles in a substance are held together by..

electrostatic attraction

Electrostatic forces occur between objects which are..

charged

Electrostatic forces are stronger if... [2 factors)

charges are closer

Opposite charges (+/—) .

attract

Like charges (+/+ or 4—)...

. repel

Elements and compounds can be represented by..

chemical formulae using the symbols from the Periodic Table and subscript numbers

If a substance exists as molecules the formula shows...

how many atoms of each element are present in one molecule

The state symbol (s) means

the substance is a solid

The state symbol (l) means

the substance is a liquid

The state symbol (g) means

the substance is a gas

Energy is needed to melt or boil a substance in order to..

overcome the electrostatic attraction between particles.

Melting and freezing take place at the.

melting point

Boiling and condensing take place at the..

boiling

A solution is formed when

A substance dissolves in another. One is usually a liquid

The substance dissolved is the

solute

The liquid into which it is dissolved is the

solvent

Solubility measures

the mass of a solute which can dissolve in a fixed quantity of solvent

Macroscopically, after dissolving the solvent

may look no different, or it may have a different colour

Microscopically, when a substance dissolves in water

its particles will separate and be surrounded by water molecules

If a substance does not dissolve it is known as

insoluble

Microscopically, when a substance does not dissolve

its particles stay together

The state symbol (aq) means

aqueous — i.e. substance is dissolved in water

Name the 6 physical processes for separate substances:

filtration, crystallisation, evaporation, separating funnel, simple & fractional distillation

Physical separation processes do not involve...

chemical reactions and no new substances are formed.

What method do you use to obtain the solvent from a solution with a solid?

Distillation

What method do you use to obtain the solute dissolved in a liquid?

Evaporation

What method do you use to separate the solid and liquid of a suspension?

Filtration

what is the liquid called after filtration?

filtrate

what is the solid called after filtration?

Residue

What do you use to separate two immiscible liquids?

Separating funnel

What method do you use to separate 2+ miscible liquids?

Fractional distillation

Name 5 diatomic elements

Hydrogen, nitrogen, fluorine, oxygen, chlorine

The 3 states of matter are

solid, liquid, gas

Is sand soluble in water?

No

Density of water

1 g/cm³

H

Hydrogen

He

Helium

Li

Lithium

Be

Beryllium

B

Boron

C

Carbon

N

Nitrogen

O

Oxygen

F

Fluorine

Ne

Neon

Na

Sodium

Mg

Magnesium

Al

Aluminum

Si

Silicon

P

Phosphorus

S

Sulfur

Cl

Chlorine

Ar

Argon

K

Potassium

Ca

Calcium

NH₂

ammonia

CO₂

carbon dioxide

CO

carbon monoxide

CH₄

Methane

NO

Nitrogen Monoxide

NO₂

nitrogen dioxide

SO₂

sulfur dioxide

SO₃

sulfur trioxide